This invention relates to a gas release device for use with an article of laboratory glassware. More particularly, the device to which the present invention relates seals the article of laboratory glassware against the entry of air from the ambient while permitting the escape of gases generated in the article.
As is well known by chemists, a separatory funnel, which is a particular article of laboratory glassware, is utilized for laboratory extractions. Typically, the separatory funnel is charged with a first liquid containing a substance which is to be extracted and a second liquid, immiscible with the first, which is to extract the substance. The contents of the separatory funnel are then vigorously shaken. While performing this operation, the chemist or technician frequently finds it convenient to hold the separatory funnel with the axis thereof generally horizontal. While thus holding the funnel, the chemist or technician may periodically interrupt the shaking to open the stopcock of the separatory funnel to release gases which may have been generated in the funnel during the mixing. For the same purpose, the chemist or technician will frequently also open the stopcock at the conclusion of the mixing operation. When the stopcock is opened, the liquid contents of the separatory funnel will not escape because the separatory funnel is being held in a tipped position and, to assure thorough mixing, is less than half full.
One disadvantage of this technique is that it requires manipulation of the stopcock while holding the separatory funnel sideways, which might cause the chemist or technician to drop the separatory funnel. Another disadvantage is that the periodic interruption of the shaking to manipulate the stopcock is timeconsuming. Moreover, one cannot simply mount the separatory funnel on a mechanical agitator, actuate the agitator and leave the funnel unattended until the agitating operation is completed. Yet another disadvantage is that if the stopcock should be opened at such time that the pressure in the separatory funnel is atmospheric or below, ambient air, which might contaminate the contents of the funnel, will be drawn into the funnel.
It is an object of the invention to provide a gas release device for airtight connection with the mouth of an article of laboratory glassware such as a separatory funnel which will be substantially free of the aforementioned disadvantages. Other objects and advantages of the invention will be apparent from the following detailed description thereof.